Oil sump air filter



July 3, 1951 G. WALLACE OIL. sun/1Pv AIR FILTER Filed June 20, 1947IWW/.wim Gord/on Wallace. l

Patented July 3, 1951 UNITED STATES PATENT -OFFICE OIL SUMP AIRFILTERGordon Wallace, Lon-g Beach, Calif.

Application June '20, 1947 Serial No. 755,841

(Cl. v18S-'15) This invention relates to an air filter of the oil sumptype particularly adaptable to internal combustion engines.

An object of my invention is to provide a novel down draft air filter inwhich dirt and other foreign substances are effectively removed from theflow of air to the engine.

Another obj ect is to provide an air filter of the character stated, inwhich there is a minimum loss of power due to impeding the flow of airto the engine.

Still another Objectis `to provide a novel means of returning the air tothe area below the air i11- take so that there is always a V.pool :.oftoil at this point and dirt is thus caught and prevented from passinginto the engine.

Still :another object is to provide a novel filter pack in the cleanerwhich can be quickly and easily removed for purposes of cleaning andrepair.

Other objects, advantages and features of :invention may appear from theaccompanying drawing, 4the subjoined detailed description and the.appended claims.

In the drawing:

Figure l is a partial sectional View of my air filter, the outer shellbeing broken away to show interior construction.

Figure 2 is a bottom plan -view of the filter pack with parts brokenaway to show the return tube construction.

Referring more particularly to the drawing, the numeral I indicates anouter case or housing, which is closed at the top by the wall 2. A pan3, ts over the bottom. of the case I, and is limited in its upwardmovement by a bead 4 formed on the case. The pan is held in position onthe case by a pair of balls 5, 5, which are secured at their upper endsto ears 6, 6, the ears being fixedly attached to the case I.

A strap l, is secured to the bottom of the pan 3, and the balls 5,engage the outer ends of the strap to hold the pan in position. Each ofthe bails 5, are provided with a thumb nut 8, which screws onto thebottom of each bail and bears against the strap l, thus holding theparts in assembled position. The pan 3, is partly filled with oil, thetop level of the oil being approximately at the bead 9, and the incomingoil strikes the surface of this oil, all of which will be furtherdescribed. The sand and dirt particles are caught by the oil and theclean oil passes upwardly through a lter pack and thence into the engineas will be subsequently described.

An intake pipe I0, is centrally positioned in the loase I, and extendsupwardly in the case and through the top wall Y2. The bottom of the pipeI0, terminates above the surface of the oil in the pan 3. An outlet pipeII, extends from the case I, adjacent the top thereof, and is connectedto the .oil intake Yof the Carburettor, all of which is usual and wellknown.

To prevent the oil in the pan 3, .from being Idrawn over into theengine, `and `also to further insure that all of the dirt -Will :beremoved from the air, vI provide Aa filter pack I2, which com- ,prisesan outer metal ring I3, and an inner sleeve I4. The sleeve I4, closelyencircles the tube I0, V.and yat outer ring I3, closely fits the case I.

A plurality of spaced screens I5, lare arranged in the lfilter pack andeach of these screens rests against one .of the inwardly projectingbeads II, .formed in the outer `ring I3. A fibrous rpacking I l, is.arranged between the screens I5, and this packing may consist ofIhai-r, lsteel Wool, or the like. The `lower end of the ring I3, is bentinwardly at the ybottom to form a cone I8. The lowerendpf the cone isformed with a depending flange 419, to which a handle 26, is secured.The handle 20 rests against the bottom of the pan 3, shown in Figure 1,thus holding the lter pack I2, in proper position. The handle 20, alsoserves as a convenient means of withdrawing the filter pack from thecase when it is desired to clean the same.

A plurality of holes 2|, extend through the cone I 8, and these holesact as relief ports so that the oil in the pan has a free verticalmovement without compressing the oil in the space between the cone I8,and the surface of the oil. A depending ring, 22, extends from the coneI8, and is spaced outwardly from the ilange I9. A return oil pipe 23,extends through the flange I9, and into the annular space between thisflange and the ring 22. The pipe 23, is open at both ends and isprovided with a pair of ports 24, adjacently center of the pipe.

A cone 25 is attached to the pipe 23, and extends downwardly. Thepurpose of this cone is to deflect the oil outwardly and away from thecenter of the air filter. In operation the incoming oil Will strike thesurface of the oil within the cone I8, with considerable velocity. Thiscauses a pressure on the surface of the oil and the oil will be forcedoutwardly and upwardly following the contour of the cone I 8, and alsofilling the space within the ring 22. This oil under pressure will thusbe forced into the ends of the pipe 23, and will return to the center ofthe filter through the ports 2li. Dirt and sand will be caught in theoil sump, and the clean oil will pass upwardly through the filter packl2, and thence into the engine.

If the incoming air has sufficient velocity, as it sometimes does, theoil could be blown entirely away from the center of the oil pan 3, thuseliminating the advantages of the bath of oil. With my return oil tube23 oil is constantly returned t0 the center of the oil pan 3, and thusthere will always be a surface of oil to trap incoming sand cr dirt. Theblast pressure of the incoming air,

when striking the oil in the bottom of the pan 3,

will force that oil outwardly and upwardly into thereof being spacedfrom the bottom of the case,

' an oil return pipe extending horizontally through the space betweenthe ring 22 and the flange I9,

The level of this oil will be above the outer open end or the transversepipe 23 and, consequently,"

this oil will tend to flow back through the pipe 23 and Ythence throughthe holes 24, partly by gravity and partly by the suction created by theair passing downwardly past the holes 24. The returning oil thus flowsdownwardly over the cone 25. It is again deflected outwardly to repeatthe above named cycle.

Having described my invention, I claim:

1. An air lter comprising an outer case, a sump in the bottom 0f thecase containing oil, a vertical intake pipe extending into the top ofsaid case and at the center of the case, said pipe terminating above thesurface of the oil, an outlet pipe extending from the case, an invertedrustroconical baille within the case, the lower edge thereofbeing spacedfrom the bottom of the case, an oil return pipe extending horizontallythrough the reduced end of said baie, said pipe having an outlet nearthe center of the case, the outer ends of said pipe being open to returnoil from the periphery of the case to adjacent the center'thereof.

2. An air ilter comprising' an outer case, a sump in the bottom of thecase containing oil, a vertical intake pipe extending into the top ofsaid case and at the center of the case, said pipe terminating above thesurface of the oil, an outlet pipe extending from the case, an invertedfrustroconical baffle within the case, the lower edge the reduced end ofsaid baffle, said pipe having an outlet near the center of the case, theouter ends of said pipe being open to return oil from the periphery ofthe case to adjacent the center thereof, said baie having relief portsextending therethrough, and a filter pack surrounding the intake pipeand extending between said pipe and the outer case.

' 3. An air iilter comprising an outer case, a sump in the bottoni ofthe case containing oil, a Vvertical intake pipe extending into the topof said case and at the center of the case, said pipe terminating abovethe surface of the oil, an outlet pipe extending from the case, aninverted frustroconical baille within the case, the lower edge thereofbeing spaced from the bottom of the case, an oil return pipe extendinghorizontally through the reduced end of said baiile, said pipe having anoutlet near the center of the case, the outer ends of said pipe beingopen to return oil from the periphery of the case to adjacent the centerthereof, said, baille having relief ports extending therethrough, and alter pack surrounding the intake pipe and extending between said pipeand the outer case, and a delecting cone xedly mounted on said pipe, theapex of said cone projecting upwardly.

GORDON WALLACE.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number YName Date 1,838,513 Wilson Dec. 29, 19312,018,493 Halstead Oct. 22, 1935 2,072,548 Donaldson Mar. 2, 19372,269,663 Hallerberg et a1. Jan. 13, 1942 2,273,210 Lowther et al Feb.17, 1942 2,342,447 Bennett et al. Feb. 22, 1944 2,387,278 Lowther Oct.23, 1945

